Cosmete can't be adapted into live actions. Guys, dropped it already
Stormlight Archive is specifically impossible. It's an alien planet, with a typically strange fauna and flora. Except by Shinovar it barely resembles earth, means almost every time they are outdoors they will need to be at a green screen (and sometimes even in doors, interacting with animals and spren)
From what I hear from my colleagues from VFX, doing things with Unreal is becoming quite a thing.
Animation would be great, but selling that to mainstream audience is a lot harder than live action show with CGI.